PURPOSE: To evaluate important material properties of six experimental resin-based restorative materials (EXP) with systematically modified resin matrices using conventional and alternative monomers in comparison with an experimental standard (ST). MATERIALS AND METHODS: Commercially available monomers were selected according to their molecular weight, functionality, viscosity, and polymerization shrinkage. ST, 71wt% filler, matrix UDMA/Bis-GMA/TTEGDMA and six EXPs with modified organic matrices but the same filler content were manufactured. Flexural strength, flexural modulus, water sorption, solubility and polymerization shrinkage of all EXPs were measured and compared with the results of ST. RESULTS: ANOVA (p<0.05) revealed significant differences among the materials and all investigated properties. Bis-GMA and UDMA were substituted by alternative monomers without losing flexural strength or modulus. Replacing the diluting monomer TTEGDMA with alternative monomers resulted in increased flexural strength. None of the experimental products with modified matrices showed increased water sorption or solubility but some even performed better than ST. Increased hygroscopic expansion and reduced shrinkage were achieved using a very hydrophilic monomer but no significant differences of water sorption and solubility in comparison with ST were found. CONCLUSION: The results indicated that there are monomers commercially available providing the same or even better properties than conventional matrices. Copyright (c) 2009 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
PURPOSE: To evaluate important material properties of six experimental resin-based restorative materials (EXP) with systematically modified resin matrices using conventional and alternative monomers in comparison with an experimental standard (ST). MATERIALS AND METHODS: Commercially available monomers were selected according to their molecular weight, functionality, viscosity, and polymerization shrinkage. ST, 71wt% filler, matrix UDMA/Bis-GMA/TTEGDMA and six EXPs with modified organic matrices but the same filler content were manufactured. Flexural strength, flexural modulus, water sorption, solubility and polymerization shrinkage of all EXPs were measured and compared with the results of ST. RESULTS: ANOVA (p<0.05) revealed significant differences among the materials and all investigated properties. Bis-GMA and UDMA were substituted by alternative monomers without losing flexural strength or modulus. Replacing the diluting monomer TTEGDMA with alternative monomers resulted in increased flexural strength. None of the experimental products with modified matrices showed increased water sorption or solubility but some even performed better than ST. Increased hygroscopic expansion and reduced shrinkage were achieved using a very hydrophilic monomer but no significant differences of water sorption and solubility in comparison with ST were found. CONCLUSION: The results indicated that there are monomers commercially available providing the same or even better properties than conventional matrices. Copyright (c) 2009 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Authors: Naresh Kumar; Muhammad S Zafar; Waheed M Dahri; Muhammad A Khan; Zohaib Khurshid; Shariq Najeeb Journal: J Taibah Univ Med Sci Date: 2018-06-06